Neutering if male, unless intended for breeding and provisions made to care for parents and offspring. Neutering females isn’t common as the operation is more complicated. Your vet will advise on neutering.

Handling daily from an early age. Guinea pigs well handled by people from a young age can learn that humans are friends and companions. Those receiving little handling when young, or roughly handled at any age, may find human contact distressing. This can be expressed as fearfulness/running away/hiding/aggression. Guinea pigs living indoors can see humans as important companions. If your guinea pig has to be kept alone you must provide companionship by interacting with them daily. Guinea pigs can develop abnormal behaviour and may suffer if left without company and nothing to do for long periods.

Places to escape from companions if they want to. Provide enough resources (e.g. shelter/food/water/hiding places) for all guinea pigs at all times. Guinea pigs are naturally sociable preferring other guinea pig company; kept together form a “pecking order”. Some animals become more dominant than others. If there aren’t enough places to spend time away from each other, they can become stressed and may bully lower ranking individuals.

Introducing to new guinea pigs gradually and under supervision, preferably somewhere new to both guinea pigs. Guinea pigs brought up together usually get on, but adult males introduced for the first time may fight. Consult a guinea pig behaviour expert if you’re unsure/have problems.

Caring for by a responsible person when you’re away to meet all their welfare needs.

Constant supervision when they’re with another animal/person who may deliberately/accidentally harm/frighten them or with a cat or dog, even if you know they’re good friends. Guinea pigs will usually be scared of cats/dogs because they’re natural predators, but if introduced carefully early in life can develop friendships.